A person marked by stupidity or foolishness.(noun)
Stupid, foolish(adjective)
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Use "dumbass" in a sentence
"Jackson Hole takes on a whole new meaning when this dumbass is around."
"Can you please just admit that that entire screed was nothing but more stupid being spewed all over the place by the dumbass from the great white north and stop with the pathetic attempts to justify and defend blatant ignorance?"
"Rab says: pezmiztick: You being a dumbass is predicated on you being a dumbass"